Attached to the pigeons leg and containing a small rolled paper message, sometimes as thin as a human hair.

Carrier pigeon message tubes were used during WW1 and WW11, during WW1 wireless communication was still in its infancy, and telephones in the theatre of war could only be used over limited distances.

Even microfilm could be transported by this means.

Carrier Pigeon Service (CPS)

The history of the use of carrier pigeons in warfare is indeed a varied and interesting one, with a long and illustrious history. It is believed that the use of carrier pigeons as a messenger service had it origins in antiquity – over three thousand years ago by the Egyptians, Persians and Romans; in 1150 A.D., the Sultan of Baghdad strapped capsules filled with papyrus sheets to the leg or back feathers of pigeons, and used them as messengers. They were used as recently as 1990, by the Iraqi Army during the First Gulf War.
Pigeons played a vital part in World War One as they proved to be an extremely reliable way of sending messages. Such was the importance of pigeons that over 100,000 were used in the war with an astonishing success rate of 95% getting through to their destination with their message. The British Army had a unit called the Carrier Pigeon Service (CPS) which was led by Lt. Col. A.H. Osman. Carrier pigeons were used by the British during the Second Battle of Ypres in May of 1915. The Carrier Pigeon Service was only used when telegraph and telephone communications failed and was soon overtaken by the development of Wireless Telegraphy (i.e. Radio), further limiting their usage; hence, they were only used for emergency or espionage purposes. The avian unit saw further success at the Battle of the Somme and at Verdun, often against screens of poisonous gas and heavy shelling from the opposition.
In October 1918, as the war neared its end, 194 American soldiers found themselves trapped by German soldiers. They were cut off from other Allied soldiers and had no working radios. The only chance they had of alerting anybody about their desperate situation was to send a pigeon with their co-ordinates attacked to its leg. The pigeon's name was Cher Ami. When released it flew 25 miles from behind German lines to the Americans headquarters. Cher Ami covered the 25 miles in just 25 minutes. The pigeon was, in fact, shot through the chest by the Germans but continued to fly home. With the "Lost Battalion's" co-ordinates, the Americans launched a rescue and the 194 men were saved. Cher Ami was awarded the Croix de Guerre with Palm for its astonishing flight. As with other pigeons, it would not have known where the American's nearest headquarters was - its natural homing instincts took over.

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Item is an American made pigeon carrying cylinder. 12 of these were carried in the larger 4 pigeon carrying boxes (PG 51) along with 2 signals corps message pads. The idea was to release 2 birds with the same message 30 minutes apart - hopefully ensuring one would get through. Pigeons were carried on RAF missions, Royal Naval and Merchant ships as well as dropped to enemy agents behind the lines. The army kept a number of lofts during the war to receive messages from these sources and despatch them as soon as possible to the relevant authorities. Still the biggest proportion of Dicken Medal recipients since its 1942 inception. .......... Paul Watson, Sheffield, 21st of January 2016